不同地质成因的边坡在土体参数统计变异性相同的情况下,由于空间变异性不同,其稳定状态并不一定相同,传统的边坡稳定性确定性分析和基于随机变量模型的边坡可靠度分析方法无法考虑坡体的特定地质成因。由地质成因估计土体参数的波动范围,从而通过土体参数波动范围这一指标把地质成因纳入边坡稳定性分析框架,提出考虑地质成因的边坡可靠度分析方法,介绍具体的分析流程,采用一维随机场模拟和验算点法完成边坡可靠度分析。算例计算结果显示岩土参数空间变异性对边坡稳定性的影响很大,由地质成因估计土体参数的波动范围,为在边坡可靠度分析中合理考虑土体参数空间变异性提供一条现实的解决途径,值得在工程应用中推广。
Because spatial variability often exists in natural soil slope,which is mainly dominated by its geologic origin under the same soil parameters statistical variability,the slope stability is not really same.Traditional deterministic slope stability analysis method and reliability slope stability analysis method based on random variable model can not deal with the geologic origin of slope mass.The scale of fluctuation of soil parameters can be estimated by its geologic origin.Thus geologic origin can be included in the slope stability analysis framework by means of scale of fluctuation of soil parameters.Reliability analysis of soil slope stability considering geologic origin employing 1D random field and first order reliability method(FORM) is proposed and its specific analysis flow is also introduced.The proposed analysis method is illustrated by an example of embankment.Example calculation results indicate that spatial variability of parameters of rock and soil has great influence on slope stability.Estimation of scale of fluctuation of soil properties through geologic origin provides a realistic solution for the reasonable consideration of spatial variability of soil parameters in reliability analysis of slope stability.The proposed method is practically applicable and quite valuable for practice.